Surgical residents' technical skill is typically evaluated from observations by experienced mentors during training; however this process is time consuming, labor intensive and subjective, and may include evaluator biases. Efforts have been made to standardize surgical trainee evaluations and eliminate bias. The most frequent performance evaluation currently used is the objective structured assessment of technical skills (OSATS).
The correlation between hand motion and surgical skill has been extensively documented over the past decade. Metrics such as smoothness of movement, velocity and acceleration, path length of the hand, entropy levels, idle time, and the comparative usage of dominant and non-dominant hands have been shown to be significantly related to surgical experience (Ahmidi 2015; D'Angelo 2015; Datta 2001, 2006; Dosis 2005; Gray 2012; Moorthy 2003; Overby 2014; Uemura 2014; Watson 2012, 2014). However, the majority of previous studies relied on synthetic models or non-surgical tasks to simplify the hand motion analysis (D'Angelo 2015; Datta 2001, 2006; Gray 2012; Moorthy 2003; Overby 2014; Uemura 2014; Watson 2012, 2014). Multiple reports have described tools to measure and track hand motion during rigid endoscopy (e.g. laparoscopy, arthroscopy) (Ahmidi 2015; Dosis 2005a, 2005b) and during use of robotic surgery devices (Reiley 2009). Tracking hand motions while using flexible endoscopes is more difficult, since operator hand movements do not translate directly into movement of the distal end of the flexible endoscope, especially in mobile environments such as the colon (Cao 2006). Hand movement tracking data is useful to assist intraoperative navigation to position acetabular implants (Digioia 1995) and for quantifying the benefits of training (Gambadauro 2012). Manual dexterity parameters, including time to perform, motion economy, hand & tool movement, and instrument path length, among others, are related to levels of surgeon experience (Ahmidi 2015; D'Angelo 2015; Datta 2001, 2006; Gray 2012).